In a large stockpot over medium heat, saute the onion, garlic, and jalapeno pepper (if using) in the olive oil.
Add the tomatoes, Italian seasoning, basil, oregano, garlic powder, salt, and sweetener.
Using a wire hand whisk, incorporate the tomato paste. Bring sauce to a boil, then reduce heat to low and simmer uncovered for 30 minutes, until the sauce has thickened to your preference.
Remove sauce from the heat and use as desired.
If desired smooth the sauce once cooled using an immersion blender or food processor.
Store any unused pasta sauce in the refrigerator for up to 2 weeks. Or, freeze up to 3 months in quart-sized freezer bags.